I will yield to Dave Girard if that is the consensus. However, the problem will be that we can not compare the castle to town or space MOCs. I know they are not using 5'2" as the height of their minifigs. Also, all my castle dimensions just shrunk by 20% !

Finally, when my mind wonders and I am walking amonst my minfigs in their castle I am politely patting the short little buggers on the head

Let them come...
They will break upon this fortress like water on rock!
---King Theoden

The models lego has used, not just for castle, but all genres have always been gross approximations or representational. This is why Castle walls are short and thinner than those in my condo. This is also why town's cars seat 1 minifig abreast.

But if you're going for a "realistic" castle just use real castle dimensions. Or go for something inbetween. You don't need to spend a fortune on bricks and be a slave to prototype by making massive walls. Go for something between, like 4 studs.

In the end, all that matters is that you think it looks good, and that it's difficult for pets or small children to destroy.

i really like that calculator, hmmmmmm.......... by it's calculations, the front facade of my cathedral in progress is 147 feet tall. the minifig is absolutely dwarfed! too bad it's on LDRAW though....... i simply dont have the money to buy all the parts necessary. i havent finished the second tower of the front facade, and i am already up over 4000 pieces! i am shooting for about 30,000 overall. maybe someday i will have the means to build it in real life...sigh. oh well, LDRAW is good enough for now, besides, i wouldnt have anywhere to put it! i will post a work in progress pic soon, when i finish the second tower and main stained glass window (all trans 1x1 plates for highest level of complexity possible!) hee hee, im a bad man .

Sounds like a wonderful creation!! I also use LDraw for my "dream" projects. I am working on a Castle right now that is approching 20K pieces. The hardest part is running the program. Ever notice how CAD programs run VARY slow?
Maybe its just my computer.